Conservation Priorities and Population Structure of Woody Medicinal Plants in an Area of <Emphasis Type="Italic">Caatinga</Emphasis> Vegetation (Pernambuco State,NE Brazil)

In spite of heavy harvesting pressure on some of the most popular medicinal plant species, there are very few published studies concerning their conservation the semi-arid region of northeastern Brazil. In light of this fact, the present work sought to evaluate the local conservation and the harvesting sustainability of medicinal plants in an region of caatinga vegetation employing a fusion of biological and cultural approaches. Ethnobotanical methodologies and techniques were employed in the community of “Riachão de “Malhada de Pedra”” (municipality of Caruaru, state of Pernambuco, Brazil) in order to document local knowledge concerning medicinal plants and to examine the availability of those plants in a caatinga vegetation fragment located near that community. A total of 21 medicinal plant species were identified in the area and classified according to ecological factors and local uses. Two plants (Ziziphus joazeiro and Myracrodruon urundeuva) stood out has having high priority for conservation efforts. Sixteen species were identified as having populations adequate for harvesting through a system of pre-determined quotas, while four species were deemed sufficiently abundant to be harvested without risk of causing significant impact on their sustainability.     

Commercial bumblebee hives to assess an anthropogenic environment for pollinator support: a case study in the region of Ghent (Belgium)

Anthropogenic changes of the environment influence the distribution and abundance of pollinators such as bumblebees and have been proposed as one of the main causes in their worldwide decline. In order to evaluate the impact of expanding anthropogenic landscapes on supporting pollinator potential, reliable tools are needed. Bombus terrestris is one of the most abundant bumblebee species in Europe, and these bumblebees are known as generalist pollinators of not only wild flowers in nature but also of crops in agriculture. For more than two decades, these bumblebees have been commercially mass reared for biological pollination in greenhouses. In this project, we placed commercial hives of the bumblebee B. terrestris containing one queen and 40 workers, in three different locations in the region of Ghent (Belgium), and the performance of these hives was followed during a 4-week period in spring 2012. In parallel, we determined the floral richness and diversity index in the chosen study sites. The sites consisted of a rich urban environment with patchy green areas opposed to an urban environment with poor landscape metrics; a third rural study site showed average positive landscape metrics. The results demonstrated that the hive biomass and numbers of workers increased significantly in the rich compared to the poor environment, providing a mechanism to discriminate between study sites. In addition, the bumblebee-collected pollen showed that the flowering plants Salix spp. and Rosaceae/Prunus spp. are dominant food sources in all anthropogenic environments during early spring. Finally, the results are discussed in relation to the optimization of the experimental setup and to the use of commercial bumblebee hives in assessing local pollinator support within any given environment.     

Biochemical changes in plant leaves as a biomarker of pollution due to anthropogenic activity

The air pollution due to anthropogenic activities seriously affected human life, vegetation, and heritage as well. The vegetation cover in and around the city mitigates the air pollution by acting as a sink for pollution. An attempt was made to evaluate biochemical changes occurred in four selected plant species, namely Azadirachta indica, Mangifera indica, Delonix regia, and Cassia fistula of residential, commercial, and industrial areas of Nagpur city in India. It was observed that the correlated values of air pollutants and plant leaves characteristics alter foliar biochemical features (i.e., chlorophyll and ascorbic acid content, pH and relative water content) of plants due to air pollution. The changes in air pollution tolerance index of plants was also estimated which revealed that these plants can be used as a biomarker of air pollution.     

Assessment Of Trampling Simulation Impacts On Native Vegetation In Mediterranean Sclerophyllous Forest

This study examines the effects of visitors on vegetation of natural semi-arid areas of Mediterranean basin using controlled experimental trampling. Impacts were assessed on days 1, 5, 15 and 30 examining presence of plant species, their cover and height in linear transects suffering a constant trampling intensity (25, 75, 100 and 200 passes/day). In addition, the study included the analysis of factors such as plant species, trampling intensity, the cumulative impact (day effect) and the type of footwear on plant variables. The results showed a decrease on plant cover and height influenced by cumulative (day) effect, an effect of trampling intensity and a different effect for each species. In contrast, shoe type affected only slightly the decrease in plant height. The evolution of plant cover revealed which species were most resistant to trampling. The disappearance of plant individuals during trampling appeared to be an impact index better than plant cover, because cover increased in some species when they were trampled thus introducing a bias.     

Native medicinal plants commercialized in Brazil – priorities for conservation

A majority of the native medicinal plants that are commercialized in Brazil are harvested from natural populations. In addition to this essentially unrestrained collecting, these plants have been heavily impacted by the cutting and the fragmentation of forest formations throughout the country. Considering the limited availability of natural resources, threats to species diversity, and the necessity of conservation efforts in light of the rapid exhaustion of natural ecosystems, it is becoming exceedingly important to establish conservation priorities. The present work sought to identify the native medicinal plants harvested for industrial purposes and to establish conservation priorities for the species of highest commercial value. To that end, a survey of Brazilian industrial products that use medicinal plants was undertaken in 54 shops in the city of Recife (Pernambuco, NE Brazil). The survey noted information concerning the commercial name of the product, its plant composition and pharmaceutical presentation, therapeutic indications, as well as the laboratory that produced it. Only native species were considered. A total of 74 different native species used to produce more than 300 types of products were encountered in the present survey. Twelve species demonstrated significant versatility (Species which had the highest numbers of different therapeutic indications and body systems), and 58.33% of these plants were trees. Destructive collecting predominates (58.11%), greatly affecting taxa collected exclusively from wild populations (86.49%). The intensive use of exclusively wild species and the destructive harvesting techniques employed in gathering them create serious problems that will threaten the availability of these resources to future generations.     

Identifying potential receptors and routes of contaminant exposure in the traditional territory of the Ouje-Bougoumou Cree: Land use and a geographical information system

Great concern has been raised with respect to the 13 traplines that constitute the traditional territory of the Ouje-Bougoumou Cree located in the James Bay region of northern Quebec, Canada, with respect to mine wastes originating from three local mines. As a result, an “Integrative Risk Assessment” was initiated consisting of three interrelated components: a comprehensive human health study, an assessment of the existing ecological/environmental database, and a land use/potential sites of concern study. In this paper, we document past and present land use in the traditional territory of the Ouje-Bougoumou Cree for 72 heads of households, including 13 tallymen, and use a Geographic Information System (GIS) to layer harvest/hunting and gathering/collecting data over known mining areas and potential sites of concern. In this way, potential receptors of contamination and routes of human exposure were identified. Areas of overlap with respect to land use activity and mining operations were relatively extensive for certain harvesting activities (e.g., beaver, Castor canadensis and various species of game birds), less so for fish harvesting (all species) and water collection, and relatively restrictive for large mammal harvesting and collection of firewood (and other collection activities). Potential receptors of contaminants associated with mining activity (e.g., fish and small mammals) and potential routes of exposure (e.g., ingestion of contaminated game and drinking of contaminated water) were identified.     

Regional data refine local predictions: modeling the distribution of plant species abundance on a portion of the central plains

Species distribution models are frequently used to predict species occurrences in novel conditions, yet few studies have examined the consequences of extrapolating locally collected data to regional landscapes. Similarly, the process of using regional data to inform local prediction for species distribution models has not been adequately evaluated. Using boosted regression trees, we examined errors associated with extrapolating models developed with locally collected abundance data to regional-scale spatial extents and associated with using regional data for predictions at a local extent for a native and non-native plant species across the northeastern central plains of Colorado. Our objectives were to compare model results and accuracy between those developed locally and extrapolated regionally, those developed regionally and extrapolated locally, and to evaluate extending species distribution modeling from predicting the probability of presence to predicting abundance. We developed models to predict the spatial distribution of plant species abundance using topographic, remotely sensed, land cover and soil taxonomic predictor variables. We compared model predicted mean and range abundance values to observed values between local and regional. We also evaluated model prediction performance based on Pearson's correlation coefficient. We show that: (1) extrapolating local models to regional extents may restrict predictions, (2) regional data can help refine and improve local predictions, and (3) boosted regression trees can be useful to model and predict plant species abundance. Regional sampling designed in concert with large sampling frameworks such as the National Ecological Observatory Network may improve our ability to monitor changes in local species abundance.     

Using species spectra to evaluate plant community conservation value along a gradient of anthropogenic disturbance

The aim of this study was to assess the impact of anthropogenic disturbance on the partitioning of plant communities (species spectra) across a landcover gradient of community types, categorizing species on the basis of their biogeographic, ecological, and conservation status. We tested a multinomial model to generate species spectra and monitor changes in plant assemblages as anthropogenic disturbance rise, as well as the usefulness of this method to assess the conservation value of a given community. Herbaceous and arborescent communities were sampled in five Azorean islands. Margins were also sampled to account for edge effects. Different multinomial models were applied to a data set of 348 plant species accounting for differences in parameter estimates among communities and/or islands. Different levels of anthropogenic disturbance produced measurable changes on species spectra. Introduced species proliferated and indigenous species declined, as anthropogenic disturbance and management intensity increased. Species assemblages of relevance other than economic (i.e., native, endemic, threatened species) were enclosed not only in natural habitats, but also in human managed arborescent habitats, which can positively contribute for the preservation of indigenous species outside remnants of natural areas, depending on management strategies. A significant presence of invasive species in margin transects of most community types will contribute to an increase in edge effect that might facilitate invasion. The multinomial model developed in this study was found to be a novel and expedient tool to characterize the species spectra at a given community and its use could be extrapolated for other assemblages or organisms, in order to evaluate and forecast the conservation value of a site.     

Monitoring of environmental parameters for CO2 sequestration: a case study of Nagpur City, India

The use of native plants was examined in three rural communities in the semi-arid of the state of Pernambuco, in northeastern Brazil. The techniques employed in the present study combined a number of different techniques of data-gathering, including semi-structured interviews, guided tour, key-informants, and participating observation, and sampling of the vegetation to evaluate the biodiversity of useful plants. A total of 61 woody species were cataloged, mostly used for construction purposes or fuel. Among the species that stood out for their local importance and multiplicity of uses were: Myracrodruon urundeuva (Engl.) Fr. All., Schinopsis brasiliensis Engl., and Anadenanthera colubrina (Vell.) Brenan. The first two species are included in Brazilian lists of threatened species. Arguments are presented for strategies of management and conservation of plant resources in the semi-arid region that seek alternatives to the use of timber species and the development of alternative non-timber resources.     

Natural regeneration of the herbaceous community in a semiarid region in Northeastern Brazil

This study aimed to describe and compare the interannual changes in the diversity and population structure of herbaceous plants in an anthropogenic area that has been regenerating for 15 years and to identify the similarities and differences in the biological attributes of the community compared with the characteristics of a regenerating conserved area. In total, 105 plots measuring 1 m² were established. In each plot, the herbaceous plants were identified, and their height and stem diameter were measured for two consecutive years. The herbaceous flora of the anthropogenic area was represented by 86 species in 70 genera and 27 families, and there were no significant differences in the average richness between years. The conserved area was represented by 71 species in 63 genera and 35 families, and there was a significant difference in the total richness between areas and between years, except when comparing the richness between the conserved area and the anthropogenic area during the second year. Considering both the anthropogenic and conserved areas, 123 herbaceous species were listed, and the similarity between areas was 60 %. For the anthropogenic area, the floristic similarity between years was 95 %, and in the fragment of the conserved area, the similarity was 74 %. The diversity and density were significantly different between years and between areas. Given these results, this study suggests that 15 years of natural regeneration for the caatinga is not sufficient to reestablish its native flora with respect to its herbaceous component.     

Influence of anthropogenic transformations of river bed on plant and macrozoobenthos communities

This study describes the influence of urban area on plant communities and benthic invertebrates inhabiting the S?upia River (northern Poland). Ten plant communities and 37 macrozoobenthos taxa were determined during four seasonal samplings at 25 sampling sites (October 2005 and January, April, and August 2006). The obtained data set was statistically evaluated in order to reveal the influence of anthropogenic transformations on the investigated communities against the background of other abiotic factors. Multivariate regression tree (MRT) method was used for vegetation, while for benthic fauna, both MRT and artificial neural network (ANN) methods were applied. The following explanatory variables were used: season, water temperature, and salinity; location of a sampling site; degree of human impact on the riverbed; microhabitat; and substrate type. MRT analyses showed significant differences in plant community structure depending on the location of a sampling site, indicating the influence of anthropogenic pressure, while macrozoobenthos composition differed significantly only between seasons. The overall ANN model proved the importance of type and location of a sampling site for the approximation of benthic fauna density. Additionally, influence of the explanatory variables on the consecutive macrozoobenthos taxa was analyzed on the basis of separate ANN.     

The potential of the Phytotoxkit microbiotest for hazard evaluation of sediments in eutrophic freshwater ecosystems

The applicability of the Phytotoxkit microbiotest for toxicity assessment of sediments in eutrophic freshwater ecosystems was evaluated. Sediments were collected from Turawa dam reservoir (southwestern Poland) which, for years, has been subjected to a marked nutrient enrichment and heavy metal contamination. The test plant species were exposed to whole sediments, solid phases of sediments, and pore waters. Phytotoxicity was estimated on the basis of seed germination and root elongation measurements, combined into an overall germination index (GI). For pore waters, the majority of GI values were not statistically different from the controls, which was consistent with chemical data. For solid phases and whole sediments, GI values showed diversified effects ranging from growth stimulation to growth inhibition. The results obtained vary depending on the plant species and the type of sediment samples. Generally, tests with solid phases of sediments showed phytostimulation, suggesting that higher amount of nutrients adsorbed on organic matter-rich sediments might conceal the inhibitory impact of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb, and Zn). However, this beneficial impact is indicative of a significant nutrient load and, with respect to aquatic ecosystems, its potential resuspention that might accelerate the reservoir eutrophication. Under appropriate conditions heavy metals exerted stronger negative impact on plants. Tests with whole sediments had a higher acidity (pH?5.85) and showed adverse effects, though plant responses vary from inhibition (Lepidium sativum) to stimulation (Sorghum saccharatum). The study demonstrated variability in toxicity of contaminated nutrient-rich sediments as well as effectiveness and usefulness of the Phytotoxkit microbiotest as a practical and reliable tool for evaluation of the hazard of eutrophic ecosystems to higher plants.     

Modelling Wetland Bird Response to Water Level Changes in the Lake Ontario – St. Lawrence River Hydrosystem

Lake Ontario and St. Lawrence River (LOSL) wetland bird abundance and diversity are greatly influenced by lake and river hydrology. Our study used an interdisciplinary ecosystem approach, blending avian and plant ecology, ecohydraulic, statistical ecology and modelling to evaluate potential impacts of water level fluctuations on indicator species representative of the wetland breeding bird assemblages in the entire LOSL freshwater system. Multi-year (2000–2003) bird surveys captured bird distribution and density in wetland habitats under varying degrees of water inandation, depth and fluctuation. Analyses revealed strong associations between estimated breeding pair densities and plant communities, water depth, and degree of water level fluctuation during the breeding season for a suite of wetland bird species using marsh, wet meadow, shrub swamp and treed swamp habitats. These quantitative associations were used to develop wetland bird performance indicators for use in a LOSL water regulation review study. Several bird species also nest at or near the water surface and are thus vulnerable to nest flooding or stranding. Changes to the seasonal hydrology of Lake Ontario and St. Lawrence River that result in an increased frequency or magnitude of these nest failure events may have a significant impact on regional population sustainability. Long term nest record databases were analyzed to create nesting flooding and stranding probability equations based on water level increases and decreases during the breeding season. These species-specific nesting relationships were incorporated into a reproduction index.Many breeding bird species were strongly associated with specific wetland plant communities. Predicted habitat suitability, as measured by estimated breeding pair density, can also change significantly within a specific wetland plant community based solely on changes in water depth during the breeding season. Three indicator species, Black Tern, Least Bittern and Virginia Rail were selected as key environmental performance indicators for alternate regulation plan comparisons.Water regulation criteria should be such that the long term diversity and abundance of wetland plant communities and frequency of spring flooding in marsh habitats during breeding are not reduced. Magnitude and frequency of water level change during the nesting season (May–July) can also adversely impact reproductive success of many wetland bird species. As such, regulation criteria that increase the seasonal magnitude and frequency of water level change may be detrimental to the long term viability of certain regional breeding bird populations.     

Can adaptive modulation of traits to urban environments facilitate Ricinus communis L. invasiveness?

This paper addresses the phenotypic variation among Ricinus communis L. populations in four urban habitat types (road verges, garbage dumps, construction debris, and natural area) in Delhi, India, by evaluating important traits such as plant height, basal circumference, seeds per plant, seed size, seed weight, specific leaf area, and reproductive index. An important biochemical marker, proline, considered as a good plant performance indicator under stress was also quantified in leaves of R. communis to evaluate its response in different habitats. Interestingly, the species showed significant variation in plant height, specific leaf area, seed size, seed weight, and leaf proline content in different habitat types. Leaf proline content was positively related to plant height, specific leaf area, and seed size while negatively related to the total number of seeds/plant. Interestingly, reproductive index, calculated as a ratio of the total number of seeds to the plant height also showed a negative relation with leaf proline content. Results indicated that R. communis exhibits adaptive modulation of growth, reproductive traits, and leaf proline content in various urban habitats which contributes to invasiveness, range expansion, and establishment of the species. The study also gives evidence of how morphological and physiological traits could directly affect invasiveness of R. communis.     

Global warming mitigation potential of biogas plants in India

Biogas technology, besides supplying energy and manure, provides an excellent opportunity for mitigation of greenhouse gas (GHG) emission and reducing global warming through substituting firewood for cooking, kerosene for lighting and cooking and chemical fertilizers. A study was undertaken to calculate (1) global warming mitigation potential (GMP) and thereby earning carbon credit of a family size biogas plant in India, (2) GMP of the existing and target biogas plants in the country and (3) atmospheric pollution reduction by a family size biogas plant. The GMP of a family size biogas plant was 9.7 t CO(2) equiv. year( - 1) and with the current price of US $10 t( - 1) CO(2) equiv., carbon credit of US $97 year( - 1) could be earned from such reduction in greenhouse gas emission under the clean development mechanism (CDM). A family size biogas plant substitutes 316 L of kerosene, 5,535 kg firewood and 4,400 kg cattle dung cake as fuels which will reduce emissions of NOx, SO(2), CO and volatile organic compounds to the atmosphere by 16.4, 11.3, 987.0 and 69.7 kg year( - 1), respectively. Presently 3.83 million biogas plants are operating in the country, which can mitigate global warming by 37 Mt CO(2) equiv. year( - 1). Government of India has a target of installing 12.34 million biogas plants by 2010. This target has a GMP of 120 Mt CO(2) equiv. year( - 1) and US $1,197 million as carbon credit under the CDM. However, if all the collectible cattle dung (225 Mt) produced in the country is used, 51.2 million family size biogas plants can be supported which will have a GMP of 496 Mt of CO(2) equiv. year( - 1) and can earn US $4,968 million as carbon credit. The reduction in global warming should encourage policy makers to promote biogas technology to combat climate change and integration of carbon revenues will help the farmers to develop biogas as a profitable activity.     

Local versus landscape spatial influence on biodiversity: a case study across five European industrialized areas

Land use change—mostly habitat loss and fragmentation—has been recognized as one of the major drivers of biodiversity loss worldwide. According to the habitat amount hypothesis, these phenomena are mostly driven by the habitat area effect. As a result, species richness is a function of both the extent of suitable habitats and their availability in the surrounding landscape, irrespective of the dimension and isolation of patches of suitable habitat. In this context, we tested how the extent of natural areas, selected as proxies of suitable habitats for biodiversity, influences species richness in highly anthropogenic landscapes. We defined five circular sampling areas of 5 km radius, including both natural reserves and anthropogenic land uses, centred in five major industrial sites in France, Italy and Germany. We monitored different biodiversity indicators for both terrestrial and aquatic ecosystems, including breeding birds, diurnal butterflies, grassland vegetation, odonata, amphibians, aquatic plants and benthic diatoms. We studied the response of the different indicators to the extent of natural land uses in the sampling area (local effect) and in the surrounding landscape (landscape effect), identified as a peripheral ring encircling the sampling area. Results showed a positive response of five out of seven biodiversity indicators, with aquatic plants and odonata responding positively to the local effect, while birds, vegetation and diatoms showed a positive response to the landscape effect. Diatoms also showed a significant combined response to both effects. We conclude that surrounding landscapes act as important biodiversity sources, increasing the local biodiversity in highly anthropogenic contexts.     

Global Attention to Turkey Due to Desertification

Desertification has recognized as an environmental problem by many international organizations such as UN, NATO and FAO. Desertification in Turkey is generally caused by incorrect land use, excessive grazing, forest fires, urbanization, industry, genetic erosion, soil erosion, salinization, and uncontrolled wild type plants picking. Due to anthropogenic destruction of forest, steppe flora gradually became dominant in Anatolia. In terms of biodiversity, Turkey has a significant importance in Europe and Middle East. Nine thousands plant species naturally grown in Turkey, one third of them are endemic. Also, endemic species of vertebrates, thrive in the lakes and marshy areas. The studies of modelling simulation of vegetation on the effects of Mediterranean climate during the Roman Classical period by using vegetation history showed that, in 2000 years BP, Mediterranean countries were more humid than today. Turkey is a special place on the global concern in terms of desertification because of biodiversity, agricultural potential, high population, social and economical structure, topographical factors and strategic regional location. Communication among scientists, decision makers and international non-profit organizations must be improved.     

淮河流域河南段水生植物多样性评价及其影响因素分析

通过对淮河流域河南段开展野外调查及室内监测,分析河流水生植物类群组成及优势物种,从多样性、丰富度、优势度、均匀度4个方面对水生植物进行健康评价,采用CCA分析法探讨影响水生植物的关键环境因素。结果表明,淮河流域河南段共有水生植物38种,隶属于25科33属,分布广泛的优势种为芦苇、水花生、金鱼藻、轮叶黑藻、水蓼、水鳖、篦齿眼子菜。针对健康评价结果,淮河流域河南段水生植物呈现病态到健康状态。分析表明河流生态系统遭受破坏,生态系统呈现不稳定状况,主要原因为水质污染及人为活动干扰强烈。根据水生植物分布与水环境因子CCA响应关系研究,影响水生植物的主要因子为TP、COD、p H、电导率、氨氮。     

Bird Species Assemblages as Indicators of Biological Integrity in Great Basin Rangeland

The study evaluates the potential for bird species assemblages to serve as indicators of biological integrity of rangelands in the Great Basin in much the same way that fish and invertebrate assemblages have been used as indicators in aquatic environments. Our approach was to identify metrics of the bird community using relatively simple sampling methods that reflect the degree of rangeland degradation and are consistent over a variety of vegetation types and geographic areas. We conducted the study in three range types (i.e., potential natural plant community types) in each of two widely separated areas of the Great Basin: south-eastern Idaho (sagebrush steppe range types) and west-central Utah (salt-desert shrub range types). Sites were selected in each range type to represent three levels of grazing impact, and in Idaho included sites modified for crested wheatgrass production. Birds were sampled by point counts on 9 100-m radius plots at 250-m spacing on each of 20 sites in each area during the breeding season. In sagebrush-steppe, 964 individuals in 8 species of passerine birds were used in analyses. Five metrics were significantly related to impact class, both when analyzed within range type and when analyzed with all range types combined. Species richness, relative abundance of shrub obligate species, and relative abundance of Brewer's sparrow were generally lower for the higher impact classes, whereas the reverse was true for dominance by a single species and for relative abundance of horned larks. In contrast, total number of individuals did not differ significantly as a function of impact class. In salt-desert shrub, a total of 843 birds in 4 species were included in analyses, 98% of which were horned larks. None of the metrics identified above was significantly related to impact class. Two metrics for breeding birds in sagebrush steppe (species richness and dominance) showed little overlap between values for the extremes of impact class, and thus they have potential as indicators of biological integrity. However, the sensitivity of these metrics appears to be greatest at the high impact end of the spectrum, which suggests they may have limited utility in distinguishing between sites having light and moderate impact.     

BIOMONITORING OF AIR POLLUTION IN A SEASONALLY DRY TROPICAL SUBURBAN AREA USING WHEAT TRANSPLANTS

Air pollution has been identified as a serious problem throughout the world which causes tremendous loss to the crops by affecting plant growth and yield. Earlier, air pollution was restricted to urban and industrial regions. Over the last few decades, however, it has become evident that pollutants can be transported over long distances and hence their impact may be felt widely over rural areas. The present study was conducted to evaluate the impact of urban air pollution on suburban agriculture with respect to the changes in photosynthetic rate, stomatal conductance, water-use efficiency, plant height, numbers of tillers, leaves, ears and seeds, chlorophyll, carotenoid, protein, phenol, ascorbic acid, nitrogen and sulphate-sulphur contents and seed weight of pot-grown wheat plants (Triticum aestivum var. HUW 468) kept at different sites around Varanasi city receiving varying levels of pollution load. Mean concentrations of were monitored. The study clearly showed that plants are negatively affected by the ambient levels of air pollutants. Reduction in various parameters directly corresponded with the air pollution levels at different sites.